The invention is directed to a fastening element assembly including a nail-like fastening element to be driven into a base or receiving material by an explosive powder charge operated driving device. The fastening element has a tip at its leading end, a head at its opposite end with a shank extending from the tip to the head.
Nail-like fastening elements are driven into a hard underlying base or receiving material, such as concrete, steel and the like, by means of an explosive powder charge operated driving device. A problem with this type of fastening element is the varying resistance to penetration of the base or receiving material. In the past, powder charges of various strengths have been used, as well as means in the fastening element for regulating the driving output, and in addition, the driving-in capacity of the driving device can, to some extent be adapted to the prevailing conditions. Due to irregularities in and variable strength of the base or receiving material, the required driving in energy in a given region can vary sharply.
Various means are known for achieving a secure attachment of a construction part on a receiving material with different penetration depths of the fastening element. Thus, for example, in the solution disclosed in DE-PS 1 500 868, a guidance sleeve with a flange at its leading end is positioned on the shank of the fastening element. When the fastening element is being inserted, the flange contacts the surface of the construction part to be secured. When the nail-like fastening element is driven in, the sleeve is displaced toward the head on the shank and, subsequently, is upset to some degree in the manner of an accordion. With such a fastening element, however, it is possible during unexpectedly high penetration resistance that the fastening element is not driven in by a sufficient amount, whereby the rear end of the sleeve does not contact the head. In such a situation, a sufficient attachment of the construction part is not insured, since the sleeve cannot be displaced axially on the shank of the fastening element.